1. Field
The following description relates to a method and an apparatus for detecting an envelope using a difference between sampling signals.
2. Description of Related Art
Envelope detection has been used to process signals in a speech processing field, an image processing field, a data communication field, and the like, in which a modulated signal is received and demodulated. The envelope detection has also been used in a field such as transmission of energy or data.
In an envelope detection method, signal processing is used, for example, a scheme of using a band-pass filter or a low-pass filter in a frequency band, a scheme of using a peak hold in an analytic signal obtained by the Hilbert transform, and the like. However, the signal processing may require a considerable circuit complexity for circuit implementation. Additionally, in a scheme of using an analog circuit, such as a diode, a capacitor, and the like, a circuit complexity is low, but it is difficult to detect a sophisticated envelope. Furthermore, an accuracy of envelope detection by biasing may be reduced, except for a scheme of using a filter in a frequency band.